Humaid says that he once heard Sayyiduna Muawiyah (may Allah be pleased with him) in Madinah Munawwarah during a sermon saying: "O people of Madinah, where have your scholars gone? I heard the Prophet (peace and blessings of Allah be upon him) say: 'This is the day of Ashura, fasting on it is not obligatory upon us, so whoever among you wishes to fast may do so, and I am fasting.' Upon this, the people also fasted."